1. Field of Invention
This invention relates generally to interconnection, and more particularly to systems, apparatus, and methods for interconnection, and to a rig mat employing same.
2. Description of Related Art
Rig mats, which are also known as rig pads and road mats, have been used, for example, for constructing roadways, camp mats, and drilling rig platforms on surfaces such as Arctic tundra, in order to provide a temporary rigid surface on which equipment such as motor vehicles can operate. Rig mats may reduce damage to the softer surface below, and may prevent motor vehicles or other objects from becoming caught in the softer surface. Conventional rig mats have been constructed with generally rectangular steel frames supporting wooden platforms within the frames, for example. Some conventional rig mats have been known to weigh approximately 3,000 pounds.
Desirably, rig mats are interconnectable, so that the rig mats may be used and reused to construct temporary surfaces of various desired dimensions. One known connector for interconnecting rig mats involves complementary “L”-shaped appendages. However, it has been found that when the surface underlying the rig mats is soft, spongy, or uneven, these “L”-shaped appendages fail to provide effective engagement because the rig mats can tip up when motor vehicles drive on or off of the mat, which may cause the mats to separate.
One variation of these “L”-shaped appendages includes retaining lips to prevent the mats from tipping and separating when a motor vehicle drives on or off one of the mats. However, this arrangement can still result in undesirably large gaps between adjacent rig mats, and has been found not to provide adequate stability against lateral sliding of adjacent rig mats. Furthermore, this arrangement has been found to be ineffective when debris, mud, ice, or snow, for example, becomes lodged in cavities defined by the appendages.